Method and apparatus for injecting auxiliary liquids into intake system of internal combustion engine



March 16, 1965 A. E. BRENNEMAN 3,173,408

METHOD AND APPARATUS FOR INJECTING AUXILIARY LIQUIDS INTO INTAKE SYSTEM OF INTERNAL COMBUSTION ENGINE Filed March 19, 1963 I I I2 b n 2| VALVE-| v I 5-CRANKCASE ALBERT E BRENNEMAN Inventor Patent Aflorney United States Patent 3,173,408 METHOD AND APPARATUS FOR INJECTIN G AUX- ILIARY LIQUIDS INTO INTAKE SYSTEM OF INTERNAL CGMB'USTHON ENGINE Albert E. Brenneman, Middletown, NJ., assignor to Esso Research and Engineering Company, a corporation of Delaware Filed Mar. 19, 1963, Ser. No. 266,383 8 Claims. (Cl. 123-119) This invention concerns an apparatus for injecting auxiliary liquids into the intake system of an internal combustion engine and, more particularly, relates to an apparatus which intermittently injects a cleaning liquid into a positive crankcase vent valve.

Unburned hydrocarbon and nitrogen oxides when emitted into the air in sufiicient quantity form a portion of the air pollution burden which is common in areas such as southern California. As is well known, exhaust gases emitted simultaneously from vehicles in a city can stimulate the formation of smog. It has been estimated that as much as 40% of the unburned hydrocarbon emission from an automobile can be eliminated by using a blow-by, or recirculation, device. With this device the crankcase blow-by fumes composed mainly of unburned hydrocarbons are pulled from the crankcase and fed into the carburetor or intake manifold, thus providing another chance for the hydrocarbons to burn in the engine.

Since the fall of 1960, many United States car companies have voluntarily installed such devices on cars made in or shipped into California. Recently the Automobile Manufacturers Association recommended to their member car manufacturers that crankcase blow-by devices be used in all 1963 car models. Thus, it is seen that blow-by devices will be used extensively.

The blow-by device consists essentially of a conduit leading from the crankcase to the intake manifold. A positive crankcase vent valve is placed in the line to regulate the flow of blow-by products to the intake manifold.

Although the blow-by device is effective when first installed, its efiiciency soon decreases and after a short time it has no effect at all in reducing air pollution. In fact, the malfunctioning of the device can increase the pollution because, where the blow-by device is used, ordinary crankcase ventilation equipment is usually eliminated.

It has been discovered that the decrease in efliciency is due to plugging of the vent valve by deposits formed by the unburned hydrocarbons. This plugging necessitates frequent disassembly, cleaning, and reassembly of the blow-by system. To assure the continuous operation of the device, a method (which obviates the necessity of disassembly, cleaning, and reassembly) is needed to keep the vent valve clean.

It is, therefore, an object of this invention to provide a method and an apparatus for automatically cleaning the vent valve.

Other objects of this invention will be found by reading the following disclosure.

The objects of this invention are attained by utilizing an apparatus which automatically and intermittently injects an auxiliary cleaning liquid, for example a solvent or detergent, into the vent valve or into the blow-by gas line leading from the crankcase to the vent valve. The cleaning liquid is injected into the vent valve in response to an increase in pressure in the intake manifold.

The figure of the drawing shows the apparatus diagrammatically.

The invention has been described briefly; it is best understood by examining the accompanying drawing wherein is shown a crankcase vent valve 1 in a blow-by 3,173,4il8 Patented Mar. 16, 1965 vapor line 3 which communicates with the crankcase 5 and extends into the intake manifold 7 which is fed fuel by the carburetor 9.

It is imperative that the area of the surface of the bellows 19 contacting the plunger 23 be substantially greater than the area of the plunger so that the force at the top of the plunger 23 will be greater than the force from within the pump cavity when the pressure increases within the manifold 7.

The above-described apparatus provides a means for intermittently injecting a cleaning fluid, such as a solvent, into the crankcase vent valve. The apparatus injects the cleaning fluid into the vent valve whenever there is a sudden increase in intake manifold pressure. This increased pressure occurs when going from a low to a high speed or from a relatively low to a high engine load.

During idling and also at low and intermediate speeds and/0r engine loads, there is a high degree of vacuum in the intake manifold. Since the intake manifold is connected with the bellows 19 by conduit 29, the vacuum in the intake manifold causes the bellows 19 to collapse. As the bellows collapses, the plunger 23 is raised within the pump body cavity. The vacuum caused in the cavity by the raising of the plunger causes the ball check valve 28 to close. The vacuum formed in the body cavity opens check valve 27, thus allowing the cleaning fluid to pass through the cleaning liquid conduit 11 from the container 13. The cleaning fluid fills the pump body cavity until the pressure is equalized. The check valve 27 prohibits the fluid from flowing back through the cleaning liquid conduit into the container. As the engine speed is increased, the pressure in the intake manifold is also increased. At sufiiciently high pressure the bellows is expanded, thus forcing the plunger into the pump body cavity which contains the cleaning liquid. This plunging action forces the liquid past check valve 28 through conduit 11 into the crankcase vent valve. This small amount of solvent will prevent deposit formation Within the crankcase vent valve and remove any deposits which might be formed by the blow-by gases passing from the crankcase 5 through the crankcase vent valve. As the engine speed decreases, the intake manifold pressure likewise decreases and the cycle starts once again.

It is desirable to supply a small amount of the cleaning liquid to the crankcase vent valve just prior to turning off the ignition so that the solvent might remain in the crankcase vent valve for a longer period of time, thus having a longer period to act upon the deposits. Thus, it is seen that just prior to turning off the ignition one need merely press the accelerator to increase the pressure in the intake manifold so as to actuate the pump to supply the fluid to the crankcase vent valve.

The normally open solenoid valve is desirable under certain circumstances. Driving conditions may be such that it is necessary to apply a cleaning liquid only when the ignition is turned off after operating the engine. Under these conditions, the switch 16 (located within the car) is closed so that current flows to the normally open solenoid valve 15 when the ignition is turned on. The valve is thereby closed and does not open again until the switch 16 is opened or the ignition is turned off. When the ignition is turned off, the valve opens thus allowing the cleaning liquid to pass into the vent valve in response to the still existing pressure in the intake manifold.

The cleaning liquid mentioned herein can be any suitable solvent, e.g. methyl ethyl ketone, diisopropyl ether, and the like, or a detergent such as those employed in lubricating oils and gasoline.

It is to be understood that a specific embodiment of this invention has been described. The invention is not to be so limited. For example, the apparatus described herein could be used to intermittently inject a tetraethyl ead solution or some other antiknock agent or the like into the intake system of an automobile engine or it might be used to inject any other liquid into various parts of an automobile engine where it would be desirable to have liquids injected intermittently rather than continuously.

What is claimed is:

1. A method of inhibiting deposit formation within a positive crankcase vent valve, said method comprising automatically injecting a small portion of a cleaning liquid into said valve, said injecting occurring in response to an increase in manifold pressure.

2. A method according to claim 1 wherein said clean ing liquid is methyl ethyl ketone.

3. A method according to claim 1 wherein said small amount is an amount suflieient to remove deposits formed by the gases passing through said valve.

4. A method according to claim 1 wherein said cleaning liquid is a solvent.

5. A method according to claim 1 wherein said cleaning liquid is a lubricating oil detergent.

6. An apparatus for injecting auxiliary liquids into the intake system of an internal combustion engine, said apparatus comprising:

(A) a container for said auxiliary liquid;

(B) pumping means for transferring said auxiliary liquid from said container to the intake system of said internal combustion engine, said pumping means comprising a bellows pump; and

(C) actuating means for starting said pumping means in response to an increase in pressure in the intake manifold of said internal combustion engine, said actuating means comprising a conduit connecting the intake manifold of said internal combustion engine with the bellows of said bellows pump.

7. An apparatus according to claim 6 wherein said bellows is connected by a conduit to said container.

8. An apparatus for injecting a cleaning liquid into. a

positive crankcase vent valve located in a blow-by device in an internal combustion engine, said apparatus comprising:

(A) a container for said cleaning liquid,

(B) pumping means for transferring said cleaning liquid from said container into said positive crankcase vent valve, and

(C) actuating means starting said pumping means in response to an increase in pressure in the intake manifold of said internal combustion engine.

References Cited inthe file of this patent UNITED STATES PATENTS 

1. A METHOD OF INHIBITING DEPOSIT FORMATION WITHIN A POSITVE CRANKCASE VENT VALVE, SAID METHOD COMPRISING AUTOMATICALLY INJECTING A SMALL PORTION OF A CLEANING LIQUID INTO SAID VALVE, SAID INJECTING OCCURRING IN RESPONSE TO AN INCREASE IN MANIFOLD PRESSURE. 